Circle Area

Easy Variables, Data Types & Input/Output
Solve in Playground →

Problem Statement

Write a C++ program to compute the area of a circle given its radius using PI = 3.14159.

Input Format

Radius (double).

Output Format

Print calculated area formatted to 2 decimal places.

Constraints

Radius > 0

Sample Input

5.0

Sample Output

78.54

Explanation

Computes circle area using PI * r * r formula.

Starter Code

#include <iostream>
#include <iomanip>

int main() {
    double r;
    if (std::cin >> r) {
        // Write your code here
    }
    return 0;
}

Limits

  • Time Limit: 1s
  • Memory Limit: 256MB

Embedded C Programming

Updated: March 15, 2026
Intermediate

Embedded systems rely on efficient low-level programming to interact directly with hardware. In this course, you will learn how to write practical Embedded C programs used in real microcontroller-based systems. Rather than focusing only on theory, this course follows a practice-driven approach. Each lesson includes hands-on coding exercises that simulate real firmware development tasks used